Many species are migratory or cover an extensive territory and may spread the virus within or between countries.
I work as hard to save a sparrow as a migratory bird or a hawk because to me all life is irreplaceable.
The third level of the dispersal strategy concerns the kind of flight to be adopted by a winged aphid: a costly migratory flight or a trivial flight which is less risky and less efficient at reducing intraspecific competition [ 20, 21].
The apparent lack of speciation events within this taxon could be the result of a lower speciation rate, a higher migratory potential, or a relatively recent expansion of this species into the western IRSs of Madagascar.
This again underscores the difference between steady state temporal and spatial responses, and demonstrates how having a diffusible element acts as a constraint (if a reversal in response is desired, as has been suggested in migratory responses) or a capability (preventing a reversal in spatial response, inspite of a biphasic steady state response to temporal stimuli).
Whether a bat species' relative brain and brain region size reflects a migratory or sedentary evolutionary history, as our data suggest, or waxes and wanes as a result of individual experience, as in some migratory birds (e.g. [ 2, 19]), are among a number of possibilities.
Whereas a part of the individual trajectory into a migratory or resident life history is determined by the environment (e.g., Olsson et al. 2006), a large part appears to be determined by underlying genotype (e.g., Jonsson 1982; Elliott 1989; Nichols et al. 2008; Hecht et al. 2013).
Another interesting concept is epithelial-mesenchymal transition (EMT), a process by which cells lose their polarized epithelial structures and concomitantly acquire a migratory or mesenchymal phenotype.
In accord with a migratory or active sprouting behaviour, sLECs displayed high VEGFR-3 and Nrp2 expression, but in contrast to iLECs showed strongly reduced Lyve-1 levels.
For instance, the downregulation of cell cell adhesion is a hallmark characteristic of epithelia mesenchymal transitions (EMT), a process by which cells lose their polarized epithelial phenotype and concomitantly acquire a migratory or mesenchymal phenotype [ 1].
